This article deals with the optimization and validation of a thermal model of photovoltaic panels integrated to buildings. The PV thermal model is implemented in the building simulation code ISOLAB and have already been the subject of previous works. The optimization is made by using the generic optimization program GenOpt. First, these two programs are presented. Secondly, the case study is presented both experimental and modeling way, and main results of previous work are given. Thirdly, the validation methodology is described. Fourthly, the coupling between ISOIAB and GenOpt is presented, and optimization and validation criteria are given. Finally, results of the experimental optimization are presented and the model is validated. (C) 2012 Elsevier B.V. All rights reserved.